DE3515398A1 - Device for testing visual acuity and binocular vision - Google Patents

Abstract

The device, according to the invention, for testing visual acuity and binocular vision is applied in an eye testing apparatus, especially for dioptoscopy. The invention is aimed at providing a device which permits testing of visual acuity and binocular vision, as well as measuring phoria in an equipment configuration. It is the object of the invention to design the device in such a way that the angles of incidence of the imaging beam paths for the optotypes into the right or left eye of a subject are variable. According to the invention, this object is achieved in that separate projection systems project the optotypes onto each retina of the subject and that the projection systems are movable independently of one another in several degrees of freedom.

Description

Device for checking visual acuity and binocular

Seeing The invention finds application in a device for eye testing especially for refraction determination.

There are devices for so-called clear-sighted refraction determination known, in which the imaging of test marks on the retina of a test person Via mirror and lens systems by one arranged in the direction of the subject's line of sight Concave mirror US-P 3 874 774) or partially mirrored flat plates (DE-OS 3 045 139) he follows. The image of a test mark is separated from both eyes by a beam ceiling presented. The necessary correction optics are projected in both systems for the most part along the same optical axes as the figure Test marks in the main plane of the test subject's eye according to the principle of mapping virtual Lenses in front of or on the cornea of the eye.

The physthalic beam splitting according to the US-P is a test binocular vision is not possible.

According to the DE-OS, the beam splitting takes place geometrically. To get a full To enable testing of binocular vision, a split test mark would have to be introduced whose center position must be adjustable. This leads to considerable technical equipment Expenditure.

The acquisition of phorias is also possible with the solutions mentioned not possible.

The requirement for a qualitative and quantitative assessment binocular vision is of much greater importance today Obtained, especially with the increase in the increased demands on the Johlsistung in many areas, e.g. B. with the growing number of screen workstations, an optimal correction of the test subject's eye is required. The possibility of Measurement of phoria and the optimal test: binocular vision is thus possible absolutely necessary.

The invention aims to eliminate the disadvantages mentioned, In particular, a device is to be created that allows the examination of the sharp and binocular vision as well as the measurement of phoria in one device configuration allowed.

The invention relates to a device for testing visual acuity and binocular vision with a projection sound system for imaging test marks on the retina of a subject and corrective lenses in front of bze. on the eyes of the subject.

The task to be solved is to find one of the above. Device so too design that the imaging beam paths for the right and left eyes of the Subjects vary in their angle of incidence in the respective eye, independently of one another and optionally the same test mark in both eyes or a different one in that eye Test mark can be presented.

According to the invention the object is achieved in that for the right and the left eye of the test person has a separate projection system Each projection system is around two mutually perpendicular axes pivoted and slidable along the axes.

The first of these axes is common to both projection systems and runs essentially horizontally0 It is correct after positioning of the subject to the device with the line connecting correspond to the eye pivot points of the test person. The one assigned to each projection system The second axis intersects the first axis at the pivot point after the setting has been made of the respective eye to be examined.

All possible rotations and displacements are advantageous both projection systems are motor-driven and the respective positions by means of Detected position sensors and fed to a central display. This can be done with a Be coupled to the computer.

The invention is explained below with reference to the schematic drawing explained in more detail, which represents a device according to the invention in the working position.

A carrier 2, which carries a frame 3, is fastened in a column 1. The carrier 2 with the device according to the invention is advantageous around the axis the column 1 pivots. The device can thus be used in front of a test person 4 be swiveled. Two support tubes 5 are attached to the frame 3, which have a common Have axis 6. In the working position, the device is oriented towards test person 4 so that that the axis 6 runs through the eye pivot points of the test subject 4. Two U-shaped rings Brackets 7 and 8 are independently displaceable on the support tubes 5 and rotatably mounted about the axis 6. On the bracket 7 is another r .rohr g with a Axis 10 fixed on which a first projector 11 ur, l the axis 10 rotatable and is mounted displaceably along the axis 10. A support tube 12 with an axis 13 is attached to your bracket 3 and carries a second projector 14. This one is in turn displaceable along the axis 13 and mounted so as to be rotatable about this. The projectors 11 and 14 are used to project test marks into an assigned test subject's eye and virtual corrective lenses in front of the test subject's eye.

The extensions of lines 7 and 8 cut in the working position the axis 6 in the respective eye pivot point of the test subject 4. on each projector 11 and 14 is each a support rod 15 and 16 attached, the partially permeable Wear mirrors 17 and 18. These serve to deflect the projection beam paths to the test subject's eyes. A forehead support 19 is parallel to the subject's line of sight 4 movably attached to the frame 3. Image guide cables 20 and 21 are used for transmission of one adjusting telescope system arranged on each side in the support tube 5 designed wild of the respective corneal vertex to a not shown Control point. This allows the operator to measure the corneal-seheitel distance of the test person observe a given justifier mark and z. B. by adjusting the jtirnstütze 19 set.

further image guide cables 22> 23 transmit the image of the respective files Subject pupil viewed through the projection beam path to the operating point. Means In the simplest case, the operator can use handles 24, 25 to open the projectors 11 and 14 move within their degrees of freedom. Known ones are advantageous for every movement Motorized drives and position encoders available, which are operated by the operator from the control panel are controllable from.

The function of the device according to the invention is described below.

I am a test subject. the device placed so that his forehead rests against the forehead support 19. The operator observes on a suitable screen on the control panel the position of the eye pupils, their mapping by the image guide cable 2, 23 is transmitted. By moving the projectors 11 and 14 along the axis 6 the alignment of the .L'upils takes place according to a crosshair or similar justifier marks.

The position of the projectors is determined by appropriate position sensors displayed on the support tube 5 and the pupillary distance can be read off. Afterward or at the same time, the height compensation is carried out by moving the projectors 11 and 14 along the axes 10 and 13, respectively, until the pupils are aligned with the crosshairs are. The height offset can then be read off.

The cornea-vertex distance is then set Move the forehead support parallel to the line of sight of the subject while observing the images of the vertex of the cornea transmitted through the image guide cables 20, 21 in relation to the corresponding justifier mark. The device is now like this aligned that the axis 6 with the line connecting the eye pivot points of the test subject coincides and the axes 10 and 13 each through the associated eye pivot point get lost. The monocular remote correction then takes place in a known manner for every eye. After this is completed, binocular vision is tested. Through the projectors 11 and 14, the test person is given special test characters (for each .uge a different deilbild) presented. According to the test person, the Projectors and 14 independently of one another around the associated axes 6, 10 and 13 The subject is swiveled to perceive the optotypes optimally.

From the registered position of the projectors can now values for the prismatic correction read off and / or registered inside the device will. While maintaining the set position of the projectors is now one possibly necessary post-correction of the distant refraction possible.

This can be followed by an examination of the stereoscopic ehns by performing the well-known test characters suitable for this, their partial images from the respective projector are transferred, follow cr. Any resulting change in the prismatic Correction is made by swiveling the projectors around the corresponding axis.

The convergence setting is used to check the behavior in the vicinity (near fraction) by pivoting the projectors 112 14 about the axes 10, 13 and moving the Images of the zest signs in the close distance through those in the projectors optical systems. Duech image of different corrective lenses in front of the respective one Eye of the test person The near fraction is carried out according to his assessment. The set values can in turn be read or

registrable.

Values that are already known can be used to speed up the investigation for refraction or phoria can be entered before the exam begins.

There is also the possibility of over-refraction, i.e.

Refraction determination through glasses worn by the test person or Contact lenses.

With a suitable design of the projectors is also an objective one Refraction determination is advantageously possible with the device according to the invention.

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Claims (2)

Claims 1. Device for testing visual acuity and binocular vision with a projection system for imaging full destarks on the retina of a Subjects and corrective lenses in front of or on the subject's cornea, marked with a gel in that there is a separate projection system for the right and left eye of the test subject for the imaging of test marks and corrective lenses is available that every projection system can be swiveled around two axes that are perpendicular to each other and along the Axes is displaceable that the first of these axes is one for both projection systems common axis running horizontally in the water is that after Positioning the device. to the test person with the connecting line between the eye pivot points of the test person and that the each projection system assigned, essentially vertical, second axis after positioning has taken place the first axis intersects in each case at the pivot point of the eye. 2. Apparatus according to claim 1, characterized in that all movements the projection systems are motorized and that the position of the projectors detected with position sensors and fed to a central display.